Hints for effective data collection (cont.)

Speed of sound

The approximate distance to the object is calculated by assuming a nominal speed of sound. However, actual speed of sound varies with several factors, most notably the air temperature.

The CBR 2™ motion detector has a built-in temperature sensor to automatically compensate for changes in the speed of sound due to the temperature of the surrounding air. The temperature conversion from 0° to 40° Celsius, at standard pressure, is fairly linear at about +0.6 meters/second per degree Celsius. The speed of sound increases from about 331 meters/second at 0° Celsius to about 355 meters/second at 40° Celsius. These speeds assume a relative humidity of 35% (dry air).

When using the EasyData App with the CBR 2™ motion detector, this temperature compensation will take place when collecting motion data. The sensor is located underneath the holes on the back of the CBR 2™ motion detector; therefore, when collecting data, do not cover these holes with something that is of a different temperature from the surrounding ambient temperature.

Using the CBR 2™ sonic motion detector without the EasyData application

You can use the CBR 2™ unit as a sonic motion detector with a CBL 2™ system or with programs other than EasyData.

Using the I/O unit-to-unit cable, the CBR 2™ motion detector can be used with graphing calculators that do not have the EasyData App installed but do have the CBL/CBR App and/or the RANGER program. The CBR 2™ motion detector will provide the same functionality as a CBR™ motion detector when sample data is collected using the CBL/CBR App and/or the RANGER program.

The CBL/CBR App can be used on most older TI-83 Plus calculators. The CBL/CBR App is available for downloading at education.ti.com and allows you to collect motion data using the I/O unit-to-unit cable on the CBR 2™ motion detector.

The RANGER program, which is part of the CBL/CBR App and available for other calculators, allows you to collect motion data using the I/O unit-to-unit cable. Many TI Explorations workbooks use the RANGER program. (The RANGER program is the only program available for use with the TI-89, TI-92 Plus, TI-89 Titanium, and Voyage™ 200 to perform activities like Ball Bounce and Graph Match.)

You can also use CBR 2™ unit as a motion sensor with your CBL 2™ data collection device. Use the DataMate App that comes with the CBL 2™ system to operate the CBR 2™ motion detector through a CBL 2™ system. A special CBL-to-CBRcable is required to use this system. For more information about this cable visit the TI webstore at education.ti.com.

© 1997, 2004, 2006 TEXAS INSTRUMENTS INCORPORATED

GETTING STARTED WITH THE CBR 2™ SONIC MOTION DETECTOR

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Texas Instruments CBR 2 manual Speed of sound

CBR 2 specifications

Texas Instruments has long been a prominent player in the field of educational technology, and the CBR 2 (Calculator-Based Ranger 2) is a testament to their commitment to enhancing the learning experience, particularly in the realms of mathematics and science. Designed to complement graphing calculators, the CBR 2 is a versatile data-collection device that empowers students and educators to explore real-world phenomena through hands-on experimentation.

One of the main features of the CBR 2 is its ability to capture a wide array of data through various sensors. The device is equipped with an array of built-in sensors that can measure motion, including speed and distance. This makes it an invaluable tool for physics experiments, allowing students to visualize concepts such as speed, acceleration, and trajectory.

The CBR 2 utilizes ultrasonic technology to detect distance through sound waves. This feature enables students to conduct experiments that demonstrate principles of sound and motion in a tangible way. With a range of up to 6 meters, the CBR 2 provides accurate and reliable measurements that can be graphically represented using compatible Texas Instruments graphing calculators.

The device is highly user-friendly, with simple interfaces that allow users to easily collect and analyze data. The integration with graphing calculators simplifies the process of data visualization, enabling students to create graphs in real time as they conduct experiments. This capability is particularly beneficial in encouraging interactive learning and fostering a deeper understanding of scientific principles.

The CBR 2 is designed to be portable and durable, making it suitable for classroom settings as well as outdoor experiments. Its compact size and lightweight construction ensure that it can be easily transported, allowing educators to take learning beyond the confines of the classroom.

The CBR 2 also supports various modes of data collection, including Event Mode, which allows users to trigger data collection based on specific events. This feature is useful in demonstrating concepts such as projectile motion and collisions, providing students with hands-on experience that enhances their learning.

In summary, Texas Instruments' CBR 2 is a powerful educational tool that enables students to collect, analyze, and visualize data in an engaging manner. With its built-in sensors, ultrasonic technology, and seamless integration with graphing calculators, the CBR 2 stands out as a versatile device that enriches the educational experience. It not only provides a platform for conducting experiments but also cultivates critical thinking skills and a deeper understanding of scientific concepts, preparing students for a future in STEM fields.